﻿/**
 * Copyright (c) 2011-2016, Mobangjack 莫帮杰 (mobangjack@foxmail.com).
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace util
{
    class LinkedFIFO<T> : IFIFO<T>
    {
        private Node<T> read;
        private Node<T> write;
        private int count;

        public LinkedFIFO()
        {
            read = new Node<T>();
            write = read;
        }

        public void Put(T item)
        {
            write.data = item;

            Node<T> node = new Node<T>();
            node.front = write;
            write.rear = node;
            write = node;
            count++;
        }

        public T Get()
        {
            T tmp = read.data;
            read = read.rear;
            count--;
            return tmp;
        }

        public T PreRead()
        {
            return read.data;
        }

        public int Count()
        {
            return count;
        }
    }
}
